Spike for footwear having rigid portion and resilient portion

ABSTRACT

A spike is operable to be removably coupled to an article of footwear. The spike includes a first portion that is substantially rigid. The spike also includes a second portion that is resilient.

FIELD

The present disclosure relates to a spike for footwear and, more particularly, to a spike for footwear having a rigid portion and a resilient portion.

BACKGROUND

This section provides background information related to the present disclosure which is not necessarily prior art.

Many types of footwear include spikes that improve traction. For instance, many running shoes include spikes that extend from the sole assembly. The spikes can penetrate into the running surface (e.g., dirt, grass, etc.) for enhancing the wearer's ability to push off from the running surface and improve his or her running performance.

In some cases, the spikes are removably connected to the sole of the footwear. For instance, the spikes can be threadably attached to the sole. Thus, the wearer can interchange the spikes to configure the footwear as desired (e.g., to include spikes of a desired length, width, material, etc.).

Typically, spikes are made of rigid metal. As such, these spikes can readily penetrate into softer running surfaces. However, these spikes are unlikely to penetrate harder surfaces, such as pavement, and the wearer may lose traction on these surfaces. For instance, portions of a single cross country race might be routed over grass, and other portions of the race might be routed over pavement. In this case, spikes would provide traction over the grassy portions of the race, but the spikes could prove to be a disadvantage over the paved portions.

SUMMARY

This section provides a general summary of the disclosure, and is not a comprehensive disclosure of its full scope or all of its features.

A spike is disclosed that is operable to be removably coupled to an article of footwear. The spike includes a first portion that is substantially rigid. The spike also includes a second portion that is resilient.

A method of manufacturing a spike that is operable for removably coupling to an article of footwear is also disclosed. The method includes providing a first portion that is substantially rigid and providing a second portion that is resilient. The method further includes chemically bonding the first and second portions together.

Moreover, an article of footwear is disclosed that includes a sole and a spike. The spike includes a first portion that is substantially rigid and a second portion that is resilient. The first and second portions are chemically bonded together. The first portion is made out of a polyether block amide, and the second portion is made out of carboxylated rubber. The first portion includes a threading for removably engaging with the sole. The second portion extends away from the first portion and terminates at a second end. A width of the second portion tapers downward in a direction from the first portion to the second end.

Further areas of applicability will become apparent from the description provided herein. The description and specific examples in this summary are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure.

DRAWINGS

The drawings described herein are for illustrative purposes only of selected embodiments and not all possible implementations, and are not intended to limit the scope of the present disclosure.

FIG. 1 is a perspective view of a pair of shoes that include spikes of the present disclosure;

FIG. 2 is a perspective view of a spike of the present disclosure;

FIG. 3 is a cross section of the spike taken along line 3-3 of FIG. 2;

FIG. 4 is a cross section of the spike according to additional exemplary embodiments;

FIG. 5 is a cross section of the spike according to additional exemplary embodiments;

FIG. 6 is a cross section of the spike according to additional exemplary embodiments;

FIG. 7 is a cross section of the spike according to additional exemplary embodiments;

FIG. 8 is a cross section of the spike according to additional exemplary embodiments;

FIGS. 9A and 9B are schematic representations of a manufacturing technique for manufacturing the spikes of the present disclosure; and

FIG. 10 is a detail view of a mold cavity for manufacturing the spikes of the present disclosure.

Corresponding reference numerals indicate corresponding parts throughout the several views of the drawings.

DETAILED DESCRIPTION

Example embodiments will now be described more fully with reference to the accompanying drawings.

Referring initially to FIG. 1, exemplary embodiments of articles of footwear 10 are illustrated. The footwear 10 can be running shoes, golf shoes, or any other type of footwear 10 without departing from the scope of the present disclosure. As shown, the footwear 10 can include an upper 12 and a sole 14. The footwear 10 can also include a midsole (not specifically shown), which provides cushioning between the upper 12 and the sole 14. Moreover, the footwear 10 can include one or more spikes 16. The spikes 16 can be operably coupled to the sole 14 and can project therefrom. The spikes 16 can be short and narrow such that the spikes 16 can readily penetrate into the ground, grass, dirt, or other surface upon which the wearer is treading.

In some embodiments, the spikes 16 can be removably coupled to the sole 14 as will be discussed in greater detail below. Thus, the spikes 16 of the footwear 10 can be interchangeable with longer or shorter spikes, with spikes of different materials, etc. However, the spikes 16 could be permanently fixed to the sole 14 in other embodiments without departing from the scope of the present disclosure. Moreover, the spikes 16 could have any suitable shape other than those shown in FIG. 1. In addition, the term “spike” is defined broadly herein to cover spikes, cleats, and other objects that project from a sole 14 of an article of footwear 10 to improve traction for the wearer.

Referring now to FIGS. 2 and 3, exemplary embodiments of the spike 16 will be discussed in greater detail. The spike 16 can include a first portion 18 and a second portion 20. The first portion 18 can be removably coupled to the sole 14, and the second portion 20 can extend and project from the sole 14. In some embodiments, the first portion 18 can be substantially hard and rigid, and the second portion 20 can be resilient (elastic, resiliently compressible, flexible, etc.). As such, the second portion 20 of the spike 16 can resiliently flex, for instance, when treading on hard surfaces (e.g., concrete, pavement, etc.) such that the wearer is less likely to lose traction. However, the rigidity of the first portion 18 can help the spike 16 to remain attached to the sole 14 of the footwear 10.

In some embodiments, the first portion 18 of the spike 16 can be made out of polymeric material. For instance, the first portion 18 can be made of a polyether block amide, such as PEBAX™, which is commercially available from Arkema, Inc. The first portion 18 can also be made of nylon or nylon-containing thermoplastic material as well. More specifically, the first portion 18 can contain at least 30% by weight of nylon. Also, it will be appreciated that the first portion 18 could be made out of any other suitable material. The first portion 18 can have a durometer between 40 and 75 on the Shore D scale. In additional embodiments, the first portion 18 can have a durometer between 45 and 85 on the Shore D scale. Accordingly, the first portion 18 can have very high hardness and can behave similar to metal, for instance, to ensure attachment to the sole 14.

Likewise, in some embodiments, the second portion 20 of the spike 16 can be made out of polymeric material. For instance, the second portion 20 can be made of a rubber, such as carboxylated rubber (i.e., a carboxyl group-containing rubber). More specifically, the second portion 20 can be made of a rubber composition which consists of 100 parts by weight of a carboxyl group-containing rubber, 100-300 parts by weight of fillers, and 1-10 parts by weight of a peroxide as a vulcanizing agent. However, the second portion 20 could be made out of any other suitable material. The second portion 20 can have a durometer between 45 and 95 on the Shore A scale. As such, the second portion 20 can be somewhat hard, but more compliant than the first portion 18.

Furthermore, the first and second portions 18, 20 can be directly bonded (chemically bonded) together without adhesives as will be discussed in greater detail below. As such, the first and second portions 18, 20 can be manufactured in a relatively efficient manner, and the spike 16 can be very durable. The materials of the first and second portions 18, 20 and the portions 18, 20 can be bonded together according to the teachings of U.S. Pat. No. 5,132,182, filed Feb. 21, 1991, issued Jul. 21, 1992, and claiming priority to DE 3818151, each of which is hereby incorporated by reference in its entirety.

Specific features of the first portion 18 will now be discussed. As shown in FIGS. 2 and 3, the first portion 18 can generally include a generally cylindrical base 22 with an outer surface 24. The outer surface 24 can include an engagement member 26 for removably engaging with the sole 14 of the footwear 10. In some embodiments, the engagement member 26 can be threading 28 such that the base 22 can be threadably attached to the sole 14 of the footwear 10. It will be appreciated, however, that the engagement member 26 could be of any other type.

The first portion 18 can also include a flat, disc-shaped first flange 30. The flange 30 can be centered on the base 22 such that the flange 30 extends radially therefrom. The flange 30 can include a substantially flat first mating surface 32 that faces opposite the base 22.

The second portion 20 can also include a substantially flat, disc-shaped second flange 34 having a second mating surface 35. The second mating surface 35 can face the first mating surface 32 and can be chemically bonded thereto without separate adhesives.

The second portion 20 can also include a tapered member 36 that extends away from the first portion 18 and the second flange 34. The tapered member 36 can be substantially centered on the second flange 34. The tapered member 36 can have any shape, such as a substantially frusto-conic shape, and can terminate at a second end 38. The width of the tapered member 36 can taper downward gradually in a direction from the first portion 18 to the second end 38.

Also, the second portion 20 can include one or more (e.g., two) keying surfaces 39. The keying surface 39 can be planar and can extend along the tapered member 36 perpendicularly from the second flange 34. The keying surface 39 can provide a flat surface against which a tool (not shown) can abut for drivingly rotating the spike 16 about its longitudinal axis X during attachment and removal from the sole 14 of the footwear 10.

Thus, the spike 16 can increase traction for the wearer of the footwear 10 by penetrating into a surface (grass, dirt, etc.). However, when treading on harder surfaces, such as concrete, the spike 16 may not penetrate. Nevertheless, the second portion 20 can resiliently compress such that traction is not reduced significantly. Also, the compression can absorb some shock loads to provide cushioned support on these harder surfaces. Moreover, the second portion 20 can resiliently recover once the wearer begins to tread on softer surfaces again such that the spike 16 can once again penetrate the softer surface. Furthermore, the first portion 18 can be rigid and hard to remain attached to the sole 14 of the footwear 10 despite this resilient deflection of the second portion 20.

Referring now to FIG. 4, additional embodiments of the spike 116 will be discussed. Components of the spike 116 that correspond to the embodiments of FIGS. 2 and 3 are identified by corresponding reference numerals, increased by 100.

As shown, the first portion 118 can include a base 122 and a first flange 130, and the second portion 120 can include a second flange 134 and a tapered member 136. In the embodiments shown, the second flange 134 can be partially embedded within the first flange 130; however, in other embodiments, the first flange 130 can be embedded within the second flange 134. As such, the mating surfaces 132, 135 can be non-planar.

Referring now to FIG. 5, additional embodiments of the spike 216 will be discussed. Components of the spike 216 that correspond to the embodiments of FIGS. 2 and 3 are identified by corresponding reference numerals, increased by 200.

The embodiments of FIG. 5 can be substantially similar to those of FIG. 4. However, the second member 220 can include a second projection 240 that is integrally connected to the second flange 234 and the tapered member 236. The second projection 240 can be substantially cylindrical with an annular rib 242 thereon. The annular rib 242 can extend continuously about the projection 240. The second projection 240 can project from the second flange 234 and through the first flange 230 to be embedded within the base 222 of the first portion 218. Thus, the mating surfaces 232, 235 can be defined between the first and second flanges 230, 234 as well as between the second projection 240 and the base 222 of the first portion 218. Thus, there is increased surface area for bonding. Also, the rib 242 projects radially from the axis to thereby provide additional mechanical fixation between the first and second portions 218, 220.

Referring now to FIG. 6, additional embodiments of the spike 316 will be discussed. Components of the spike 316 that correspond to the embodiments of FIGS. 2 and 3 are identified by corresponding reference numerals, increased by 300.

As shown, the first portion 318 can include a first projection 344 that is dome shaped and that is integrally connected to the first flange 330 and the base 322. The first projection 344 can project from the first flange 330 to be embedded within the second portion 320. Thus, the mating surfaces 332, 335 can be defined between the first and second flanges 330, 334 as well as between the first projection 344 and the interior of the tapered member 336. Thus, there is increased surface area for bonding between the first and second portions 318, 320.

Referring now to FIG. 7, additional embodiments of the spike 416 will be discussed. Components of the spike 416 that correspond to the embodiments of FIGS. 2 and 3 are identified by corresponding reference numerals, increased by 400.

The embodiments of FIG. 7 can be substantially similar to those of FIG. 6. However, the first projection 444 can include one or more ribs 446 that extend radially therefrom. In the embodiments illustrated, there are a plurality of ribs 446 having generally triangular cross sections; however, the ribs 446 could have any suitable shape. The ribs 446 (ribbed mating surface) can increase the surface area of the mating surfaces 432, 435 between the first and second members 418, 420, to strengthen bonding between the first and second portions 418, 420. Also, it will be appreciated that the ribs 446 could be included on the second portion 420 and can be embedded in and bonded to the first portion 418 without departing from the scope of the present disclosure.

Referring now to FIG. 8, additional embodiments of the spike 516 are illustrated. Components of the spike 516 that correspond to the embodiments of FIGS. 2 and 3 are identified by corresponding reference numerals, increased by 500.

As shown, the first portion 518 can be substantially similar to the embodiments of FIG. 3. Also, the second portion 520 can include the second flange 534 with the mating surface 535 and an outer surface 550 that is opposite the mating surface 535. The second portion 520 can also include an annular ridge 552 that projects from a periphery of the outer surface 550 away from the first portion 518. Moreover, the second portion 520 can include a central projection 554 that is centered on the second flange 534 and that projects away from the first portion 518. The annular ridge 552 can continuously encircle the projection 554. Also, the central projection 554 can be conic or frusto-conic in shape.

Referring now to FIGS. 9A, 9B, and 10, a method of manufacturing the spikes 616 are illustrated according to exemplary embodiments. Components that correspond to the embodiments of FIGS. 2 and 3 are identified by corresponding reference numerals, increased by 600.

Generally, the spikes 616 can be formed via transfer compression molding and bonding the first and second portions 618, 620 together. As shown in FIG. 9A, a top, middle, and bottom plate 660, 670, 680 can be provided. The top plate 660 can include one or more (e.g., three) plungers 662 that project downwardly therefrom. The middle plate 670 can include a corresponding number of openings 664. The openings 664 can be shaped according to that of the plungers 662. The middle plate 670 can also include feed-through passages 666 that are fluidly connected to corresponding openings 664. The passages 666 can be much narrower than the openings 664. The middle plate 670 can further include mold cavities 668 that are in fluid connection with corresponding ones of the passages 666. The mold cavities 668 can be shaped according to the second portion 620 of the spikes 616. The bottom plate 680 can include receptacles 672 that are each shaped to receive and hold pre-formed first portions 618 of the spikes 616.

The first portions 618 can be formed by conventional injection molding processes and then positioned within respective receptacles 672 of the bottom plate 680. Then, the middle plate 670 can be mated against the bottom plate 680 (FIG. 9B), and flowable material 682 of the second portion 620 can be introduced into the openings 664. Then, as shown in FIG. 10, the top plate 660 can be mated against the middle plate 670 such that the plungers 662 push the material 682 into the mold cavity 668 (i.e., the material 682 can flow into the mold cavity 668). Upon curing, the first and second portions 618, 620 can be chemically bonded with each other, for instance, as described in U.S. Pat. No. 5,132,182, filed Feb. 21, 1991, issued Jul. 21, 1992, and claiming priority to DE 3818151, each of which is hereby incorporated by reference in its entirety. Then, the plates 660, 670, 680 can be separated, and the spikes 616 can be removed therefrom. Accordingly, the spikes 616 can be manufactured in an efficient, cost effective, and repeatable manner.

The foregoing description of the embodiments has been provided for purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but, where applicable, are interchangeable and can be used in a selected embodiment, even if not specifically shown or described. The same may also be varied in many ways. Such variations are not to be regarded as a departure from the disclosure, and all such modifications are intended to be included within the scope of the disclosure. 

What is claimed is:
 1. A spike operable to be removably coupled to an article of footwear comprising: a first portion that is substantially rigid; and a second portion that is resilient.
 2. The spike of claim 1, wherein the first and second portions are chemically bonded together.
 3. The spike of claim 1, wherein the first and second portions are both made out of a polymeric material.
 4. The spike of claim 3, wherein the first portion is made out of polyether block amide and the second portion is made of rubber.
 5. The spike of claim 4, wherein the second portion is made out of carboxylated rubber.
 6. The spike of claim 1, wherein the first portion includes an engagement member operable for removably engaging with a sole of the article of footwear.
 7. The spike of claim 6, wherein the engagement member includes a threading.
 8. The spike of claim 1, wherein the second portion extends away from the first portion and terminates at a second end, and wherein a width of the second portion tapers downward in a direction from the first portion to the second end.
 9. The spike of claim 1, wherein the first portion includes a first mating surface and the second portion includes a second mating surface, the first and second mating surfaces being bonded together, the first and second mating surfaces being substantially flat.
 10. The spike of claim 1, wherein one of the first and second portions is partially embedded within the other of the first and second portions.
 11. The spike of claim 10, wherein the one of the first and second portions includes a ribbed mating surface that is embedded and bonded to the other of the first and second portions.
 12. The spike of claim 1, wherein the second portion includes a mating surface and an outer surface, the mating surface being bonded to the first portion and the outer surface being opposite the mating surface, the outer surface including an annular ridge and a central projection, the annular ridge encircling the central projection.
 13. A method of manufacturing a spike that is operable for removably coupling to an article of footwear comprising: providing a first portion that is substantially rigid; providing a second portion that is resilient; and chemically bonding the first and second portions together.
 14. The method of claim 13, wherein chemically bonding the first and second portions together includes transfer compression molding the first and second portions together.
 15. The method of claim 14, wherein transfer compression molding includes flowing a second material of the second portion to a pre-formed first portion, and molding the second portion from the second material while chemically bonding the second portion to the first portion.
 16. The method of claim 15, further comprising molding the first portion, positioning the first portion in a mold, and flowing the second material into the mold to the first portion.
 17. The method of claim 13, wherein the first and second portions are both made out of a polymeric material.
 18. The method of claim 17, wherein the first portion is made out of polyether block amide and the second portion is made of rubber.
 19. The method of claim 18, wherein the second portion is made out of carboxylated rubber.
 20. An article of footwear comprising: a sole; and a spike that includes a first portion that is substantially rigid and a second portion that is resilient, the first and second portions being chemically bonded together, the first portion being made out of polyether block amide, and the second portion being made out of carboxylated rubber, the first portion including a threading for removably engaging with the sole, the second portion extending away from the first portion and terminating at a second end, a width of the second portion tapering downward in a direction from the first portion to the second end. 